In reciprocating devices such as pumps, compressors and engines, pistons are driven or drive a crankshaft. Specifically, a crank located on the crankshaft coacts with a connecting rod which is connected to a piston through a wrist pin. The piston is intended to only have reciprocating movement in its bore while the crankshaft and its crank(s) are intended to rotate. As a result, the crankshaft and crank rotate within the connecting rod which is moved thereby and the wrist pin provides a pivoted connection between the piston and piston rod. In assembling such reciprocating devices it is common to have a blind assembly of some of the members. For wrist pins, assembly involves placing them in a diametrical bore in the piston with a diametrical bore in the connecting rod forming a continuous bore with the diametrical piston bore. Circumferential grooves are formed at the ends of the diametrical piston bore and the wrist pin such that snap rings can be placed over the ends of the wrist pin and into the circumferential grooves and thereby prevent radial movement of the wrist pin. In such an assembly, it is not uncommon for a snap ring or the like to be dropped and fall into the device. Retrieval, if possible, often takes a significant amount of time while the continued presence of the loose part in an assembled device may cause failure of the device.